Method of binding the synthetic resinous wall of an opening to a metal insert

ABSTRACT

A method of connecting a thermoplastic synthetic resinous wall of an opening with a metal insert which involves placing the insert in the opening with one end thereof extending beyond the edge of the opening and bending the extended portion of the insert by a rolling or flanging operation to form a bead over the edge of the opening and to simultaneously develop sufficient frictional heat to fuse the resin and seal the insert to the wall around the opening.

United States Patent [1 1 Rudolf Zlotek, Mutters b/lnnsbruck, AustriaAssignee: Willi Sceber, Kardaun (Bozen), Italy Filed: Nov. 5, 1971 Appl.No.: 196,131

Inventor:

Foreign Application Priority Data Nov. 9, 1970 Germany P 20 55 018.9

US. Cl. 29/400, 29/470.3, 29/511, 156/73, 220/86 Int. Cl... B23p 17/00,B23k 27/00, 823p 11/00 Field of Search 29/400 D, 470.3, 29/451, 400 R,511; 156/73; 220/86 [56] References Cited UNITED STATES PATENTS3,002,871 10/1961 Tramm et a1. 156/73 Zlotek Nov. 20, 1973 [54] METHODOF BINDING THE SYNTHETIC 3,161,330 12/1964 Sagarin et a1. 29 470.3RESINOUS WALL OF AN OPENING TO A i322 g z 29,451

, we et METAL INSERT 3,695,651 10/1972 Stuck 29/149.5 B X PrimaryExaminer-Thomas H. Eager Att0rneyRichard K. Stevens et a1.

[57] ABSTRACT A method of connecting a thermoplastic synthetic resinouswall of an opening with a metal insert which involves placing the insertin the opening with one end thereof extending beyond the edge of theopening and bending the extended portion of the insert by a rolling orflanging operation to form a bead over the edge of the opening and tosimultaneously develop sufficient frictional heat to fuse the resin andseal the insert to the wall around the opening.

2 Claims, 1 Drawing Figure METHOD OF BINDING THE SYNTHETIC RESINOUS WALLOF AN OPENING TO A METAL INSERT This invention relates generally tocontainers and more particularly to a filler neck for containers suchas, for example, cooling water overflow or header tanks and fuel tanksfor motor vehicles. The invention also relates to a method of producinga homogeneous connection between a component of thermoplastic syntheticresin or polyester and a metal component that surrounds it, especiallybetween the wall of a container of thermoplastic synthetic resin orpolyester and a filler neck of metal, to produce a filler neck assemblyfor the container.

Hitherto attempts to produce a tight and rigid connection between ametal part and an adjacent part of a thermoplastic synthetic resin havebeen unsuccessful. An object of the invention is to make this possible,particularly in filler necks for containers which also may be made of apolyester.

The objects of the invention are accomplished by providing a method forconnecting the rim of an opening in a thermoplastic synthetic resinouscontainer with a metallic tubular neck inserted in the opening whereinan end of the neck which protrudes from the opening abovethe edgethereof is flared outwardly over the edge and the heat developed byworking the metal fuses the resin which sticks to the metal and connectsthe tube together. At least one sealing ring, preferably resilient, maybe provided between the opening and the filler neck tube.

According to a further preferred feature of the invention the fillerneck has a cup-shaped portion attached to a collar of reduced diameterthat projects into the opening in the container wall. In this case thecollar is preferably formed as a separate component and securelyconnected to the cup-shaped part of the filler neck tube, preferablyhard-soldered. The cup-shaped part of the filler neck tube can overlie asealing ring on the wall of the container, through which the collarextends. Additionally, or instead of this, the collar may be surroundedby an O-ring arranged in an annular groove in the wall of the containerabout the opening.

In a preferred embodiment of the invention, a rim or flange is providedaround the mouth of the tiller neck to provide means for closing theneck with a suitable cap. An annular bead is formed on the wall of thecontainer to encircle an opening which combines with the bore of thecollar attached to the cup-shaped upper portion of the tiller neck todefine the opening or entrance to the container.

A homogeneous connection is formed between the thermoplastic syntheticresinous or polyester container wall and the collar of the tiller neckby bending the wall of the collar at its open edge to form an annularflange over the adjacent edge of the container wall and melt thesurrounding thermoplastic synthetic resin or polyester with heatdeveloped by bending the metal.

Referring now to the drawing, the embodiment of the inventionillustrated therein is disposed in an opening 1 in thermoplasticresinous or polyester wall 2 of a container which may be a header tank,a fuel tank for an automobile or the like. Only that portion of theresinous container wall immediately adjacent the opening 1 is shownbecause the remainder of the container may be of any desirableconfiguration.

Opening 1 is surrounded adjacent the interior of the container by anedge 11 of the container wall 2. An external cylindrical mouth portionof greater diameter is surrounded by a head or rim 6 integral with theremainder of wall 2. The vertical inner surface of annular rim 6 and thevertical inner surface of edge 11 of wall 2 join with the horizontalflat surface of an intermediate shoulder 15 to form a step-like wallabout opening 1.

Filler neck or tube 3 is a metallic insert in opening 1 of container 2.Filler neck 3 is composed of a cupshaped exposed portion having acylindrical wall 16 and a bottom 17 which enclose an opening 5. Anopening in the bottom of the cup-shaped portion has an externaldepending annular rim l8 thereabout. A collar 4 is disposed about rim 18with its wall hard-soldered or otherwise secured to the outer surface ofrim 18. The external diameter of the cup-shaped member is substantiallythe same as the diameter of opening 1 between the inner surfaces of bead6 so it fits snugly in the opening. Bottom 17 is disposed on shoulder 15and the external diameter of rim 18 is somewhat less than that ofopening 1 between the edges of the container wall 2 in order that thewall of collar 4 may be disposed therebetween. The upper end of wall 16is rolled back upon itself to form annular U-shaped flange or rolled rim14 about the mouth of the cup-shaped member. A suitable cap for closingopening 5 may be secured with a bayonet type connection to flange 14. Alateral connecting pipe 13 to be used for venting or other purposes isprovided on wall 16.

A rubber sealing ring 7 is disposed about collar 4 and between bottom 14and the surface of shoulder 15. A rubber O-ring 8 about collar 4 iscompressed in an annular groove 9 in wall 2 between rubber ring 7 andcollar 4.

The free edge 10 of collar 4 is flared outwardly about the edge 11 ofwall 2 surrounding opening 1.

The sealing ring 7 and O-ring 8 are compressed by the forces in thedirection of the longitudinal axis 12 produced by the flanging orbeading over of the edge 10 of collar 4 to form a seal in the plane ofthe annular step between the collar 4 and the bottom of the cupshapedmember.

The connection of neck 3 and collar 4 to wall 2 is resilient so that noloosening of these components from each other occurs with variations intemperature. Likewise, sealing failures are avoided.

Neck 3 is attached to container wall 2 of thermoplastic synthetic resinor a polyester by first placing sealing ring 7 and the O-ring 8 aboutcollar 4. Collar 4 is then inserted in opening 1 and its free edge 10 ismechanically flanged or beaded over the bead-like shaped edge 11 bymeans of a rolling or flanging device. The frictional heat developedduring this operation fuses the thermoplastic synthetic resin or thepolyester of wall 2 in the region of opening 1 which flows and sealscollar 4 to the wall 2 around the opening 1. The resulting homogeneousconnection does not change with the conditions arising in the containerenclosed by wall 2 which may be subjected to pressures of up to about2.5 atmospheres and temperatures of up to about C.

The container wallsmay be any suitable thermoplastic resin which willfuse as the wall of collar 4 is flanged thereabout such as, for example,polyethylene, polyvinyl chloride or the like. The filler neck may besteel or any suitable alloy. The container walls may instead of this beof a suitable polyester which will fuse as the wall of collar 4 isflanged thereabout.

Although the invention has been described in detail for the purpose ofillustration, it is to be understood that such detail is solely for thatpurpose and that variations can be made by those skilled in the artwithout departing from the spirit and scope of the invention except asit may be limited by the claims.

I claim:

1. A method of making a homogeneous connection between contactingsurfaces of a thermoplastic synthetic resin about an opening and a metalinsert in the is polyethylene, polyvinyl chloride or a polyester.

1. A method of making a homogeneous connection between contactingsurfaces of a thermoplastic synthetic resin about an opening and a metalinsert in the opening which comprises a. disposing the metal insert inthe opening with one end extending out of the opening, and b. flangingsaid end which extends out of the opening with a rolling or flangingdevice so that said end is beaded over the edge of the opening whilesimultaneously developing frictional heat and fusing the thermoplasticresin and causing it to flow and seal the insert to the wall around theopening.
 2. The method of claim 1 wherein the synthetic resin ispolyethylene, polyvinyl chloride or a polyester.